2020 Global Year: Interview with the Co-Chair

Preventing Pain: A Conversation with Dr. Esther Pogatzki-Zahn

Esther Pogatzki-Zahn, MD, PhD, is Professor of Anesthesia and Pain Management, and Head of Acute Pain Service at University Hospital Muenster. She is also  Principle Investigator/Head of Pain Research group “Translational Pain Research” at the University Hospital Muenster, Germany. Here she talks with IASP about her career, pain prevention, and the future of pain research and management.

IASP: How did you get started in pain research? What do you do in your current job?

Pogatzki-Zahn: I started my work as an anesthesiologist in 1995 after finishing medical school. At this time, my goal was to be a pain physician, and I was very keen to go into pain research as well. I was inspired by many famous pain researchers at that time and was looking to do a two-year postdoc in one of their labs. Unfortunately, when I visited some of these labs, I was a bit disappointed that what had been done there was not that close to clinical aspects of pain. It is not quite clear to me (because I was very young at that time and did not know the field well) how or why I ended up at the University of Iowa in Iowa City, Iowa, USA, in a laboratory with Tim Brennan. Today he is well known as one of the founders of the “postsurgical basic science” scene.

When I started my postdoc position in 1989, the community just started to pay attention to what he was doing. The idea was to develop and characterize models of postoperative (incisional) pain and to investigate the neurophathology behind it. I am sure, that my research career would not be the same without my time in Tim’s lab as well as in Gerry Gebhart’s lab in the University of Iowa’s physiology department. Personally, Tim and Gerry inspired me to do meaningful research, think earnestly about what has been done so far, how to interpret (my own and others) results and where to go next. All this was basic science stuff – very far away from patients at first glance. However, because Tim was an anesthesiologist as well, we tried to be as close as possible to research questions based on clinically relevant topics (e.g. postoperative pain at the underlying mechanisms a well as the reason why it gets chronic). After finishing my postdoc in Tim and Jerry’s labs after 3 years (instead of 2), I joined another neuroscience lab for almost 2 years in Baltimore, Maryland, USA at Johns’ Hopkins University where I again learned many research aspects from which I still benefit today.

Since then, I have been leading my own laboratory in Muenster—splitting my time between pain physician and researcher. Such an approach gives me the great opportunity to still see patients and have an idea about their needs and, on the other hand, enables me to implement the essential questions in scientific studies. To translate well from basic science to human science to patients, I added a number of research approaches in my laboratory like human psychophysical (QST, CPM) and clinical studies with patients (all basically related to acute pain as well as chronification of pain). Together, I hope, that such a translational approach is able to provide clinically relevant answers from preclinical studies that, in the future, better translate to the clinic, improve treatment and prevent the chronification of pain.

Have your research interests changed throughout your career? What are you currently studying?

My research focus is still the same compared to 20 years ago – although the way of investigating it changed quite a bit and shifted towards a more translational research approach. For example, we are trying to study the same mechanisms relevant for a certain pain condition in humans as well as in basic science studies and only those mechanisms which overlap will be further studied in depths. In basic science studies, we are using new research tools which were not available 20 years ago like proteomics and network analysis in imaging studies.These tools might lead to a better understanding of certain pathways related to the chronification of pain.

One additional change during the last 10 years was a move from only investigating acute and chronic pain conditions to studies investigating the transition from acute to chronic pain and the pathways and mechanisms leading to this. For example, we are currently investigating, in 3 large multicenter trials, mechanisms relating to why patients of certain diseases develop chronic pain and others do not. We are investigating the mechanisms (the protective ones in patients not developing chronic pain and the ones leading to chronic pain), treatment responders and non-responders, and prevention of the transition process. In clinical trials, we are trying to understand if interdisciplinary approaches are able to prevent chronification, which parts and treatments are important, and which parts do not prevent pain from getting chronic if applied through an interdisciplinary approach. And, last but not least, such approaches need to be studied in situations even if the pain is not yet chronic to prevent chronification while it is still in an early phase.

What do you think are or will be the next hot topics in pain research and management?

There are many new and interesting topics in pain research and management. One aspect, certainly in the research field, is the identification of responders and non-responders for treatments in almost all pain fields. In addition, the early identification of patients with a high risk of developing chronic pain from acute pain is highly needed and research is already in progress to, hopefully, answer this question. In fact, there will probably be different answers for different conditions.

Another hot topic, in my view, is the role of an interdisciplinary assessment and treatment approach to prevent pain. For treatment of chronic pain, there is already an idea about the effectiveness of an interdisciplinary treatment approach. In this regard, I really like the new definition of an IASP task force about such an approach: They define an interdisciplinary treatment as a“… multimodal treatment provided by a multidisciplinary team collaborating in assessment and treatment using a shared biopsychosocial model and goals.” In my view, we need such an approach not only for treatment but also for the prevention of chronification. Currently, there are some hints showing that such an approach works. If chronic pain is already established, in many cases, pain and its consequences can then only be reduced and a real cure with freedom from pain is often already hopeless. We need to realize that the prevention of chronification is the only option to stop an increase in the number of patients suffering from pain worldwide. Our research needs to target this idea more sufficiently. Lastly, we need to ask patients what their needs are and focus on those. Research of the future in pain medicine must involve patients as well.

Can you explain what translational pain research is and how it benefits pain patients and the general public?

As indicated above, translational pain research is the process of applying clinical related pain questions to basic science studies, human studies and studies in patients. Together, the results and knowledge gathered from these studies can address critical medical needs in pain patients and improve outcomes of patients with pain. More specifically speaking, it might be helpful to identify new molecules in basic science studies, but if these molecules do not exist in humans (seems clear but it is not always the case, an example is COX-3) or do not relate to pain in humans, further studies targeting this molecules are useless. Thus, research questions need well-designed studies and careful approaches to investigate really innovative mechanisms that are useful for the clinic. As I pointed out above, the best is to combine preclinical and clinical experiments, and be able to investigate the same pain-related aspects in patients, human volunteers and in preclinical basic science studies. Here, we need creative and innovative changes in basic science. For example, when I started my research, the assessment of pain behavior in basic science studies was primarily based on evoked responses to sensory stimuli (e.g. reflex withdrawal response to pin pricks and heat). Nowadays, we, and others, are measuring more complex, ethologically relevant behaviors that might be affected by pain. For example, home-cage monitoring of certain behaviors representing emotional and affective components of pain and the general well-being that can be affected by pain. We are also measuring more clinical relevant behaviors of certain etiologies (e.g. impairment of walking after surgery in rodents related to movement-evoked pain after surgery in patients), and are trying to investigate behaviors referring to spontaneous pain. Only this can help to study mechanisms really relevant for patients. Definitively, we are not able to study everything in humans for ethical issues; however, pure basic science approaches need to be designed in a way that translates well to patients, are important for humans, and focus on those aspects that are meaningful for the patients with pain.

As a pain researcher, how do you communicate progress in the field so that those who are living with pain can remain hopeful about the future?

I am very fortune to see patients with pain every day. Here, I take my research questions and discuss with them aspects they would like to address.  In addition, I try to bring new research findings back to patients. For example, I treat patients in an evidence-based approach but individually by targeting their needs, and incorporate new aspects as soon as there is something that has been shown to be effective and is approved and/or recommended. In addition, I am involved in guideline development for pain management and try to “translate” guidelines to patients by communicating them with patient representatives and patient advocates.  Nowadays, we have patient representatives getting involved in research projects and the development of clinical studies. Within societies, we discuss patients’ needs with them and are very happy that we have developed some new platforms where we meet and discuss pain-related issues.

What are some general strategies for pain prevention for the public?

As soon as chronic pain develops, it is very important to get connected with specialists in the pain field. In addition, resting, sitting at home and starting to avoid participation in social and work lives can be counterproductive. The best pain prevention involves obtaining strategies (not only medication) to be able to reduce pain-related symptoms, participating in programs “fighting” against the pain (such as physical exercise programs developed for certain diseases), and avoiding doctor hopping to get an idea about the reason behind the pain after a good medical diagnosis has been conducted. In addition, joining patient support groups related to pain or the related disease is helpful for a number of patients.

How can general practitioners help patients with strategies for pain prevention? How about pain specialists or other specialty practitioners such as rheumatologists?

Pain prevention was not well-taught in medical education several years ago, and what was taught is not what seems to work based upon current research. Thus, it is very important to teach general practitioners new approaches including what they can do as first-line responders and when to approach a specialist. Primary prevention might focus on exercise and workouts in general and especially in those experiencing a pain episode, like low back pain, and recovered from this (to prevent recurrence). In addition, following clinical relevant risk factors by red (biological) and yellow (psychosocial) flags for musculoskeletal pain is the most common construct, added by blue (occupational), black (compensation) and white (socio-cultural) flags. Here, more specific prevention targeting the risk factors might be of benefit. Screening instruments are available, especially for back pain, and primary evidence demonstrates that subgrouping patients regarding their risk for chronification and specifically tailored treatment is effective at short and middle term. Education in preventing pain from becoming chronic seems to be effective as well.  If pain is already chronic, or is becoming chronic, it is best to consult a specialist. At this point, general practitioners need to realize (and not too late) that they are not the ones any more able to help.

How have you seen pain prevention strategies change throughout your career?

For everybody today it is clear that pain treatment, such as with opioids, is not the Holy Grail to prevent pain from getting chronic or to treat pain. We are gaining more and more knowledge about how to prevent pain in a more interdisciplinary way pain and the kind of preventive strategies that are effective. However, there is still a long way to go before we know what is beneficial, how long and who is providing what type of treatment, which combinations are best and which patients respond to which kind of preventive strategies. I am very glad that the path is paved for investigating this. Still, healthcare systems do not realize that preventive is more effective than treatment and that investing in this type of pain-related healthcare strategy is more, or at least similarly, effective to help patients and society.  We need to move on to address this aspect, and IASP is doing it through the Global Year for the Prevention of Pain.